/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements.  See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License.  You may obtain a copy of the License at
*
*     http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package javax.servlet.http;

import java.util.EventListener;

/**
 * HttpSessionAttributeListener在HttpSession中添加、移除或更改属性值时触发
 *
 * 可以实现此侦听器接口，以便获取此web应用程序中会话的属性列表更改的通知.
 *
 * This listener interface can be implemented in order to
 * get notifications of changes to the attribute lists of sessions within
 * this web application.
 * @since	v 2.3
 */

public interface HttpSessionAttributeListener extends EventListener {
	/**
	 * 属性已添加到会话的通知.在添加属性后调用.
	 * Notification that an attribute has been added to a session. Called after the attribute is added.
	 */
    public void attributeAdded ( HttpSessionBindingEvent se );
	/**
	 * 已从会话中删除属性的通知.在移除属性后调用.
	 * Notification that an attribute has been removed from a session. Called after the attribute is removed.
	 */
    public void attributeRemoved ( HttpSessionBindingEvent se );
	/**
	 * 通知中的属性已被替换.在替换属性后调用.
	 * Notification that an attribute has been replaced in a session. Called after the attribute is replaced.
	 */
    public void attributeReplaced ( HttpSessionBindingEvent se );

}

